ASTM B729 Seamless UNS N08020 Nickel Alloy Pipe and Tube
- Grade: UNS N08020, UNS N08026, UNS N08024
- Outside Diameter (OD): 6.35-152.4mm
- Wall Thickness (WT) : 1.65-8.56mm
Features
ASTM B729 UNS N08020 Seamless Nickel Alloy Pipe and Tube
Chemical Composition (wt.%)
| Element | UNS N08020 | UNS N08026 | UNS N08024 |
|---|---|---|---|
| Carbon (max) | 0.07 | 0.03 | 0.03 |
| Manganese (max) | 2.00 | 1.00 | 1.00 |
| Phosphorus (max) | 0.045 | 0.03 | 0.035 |
| Sulfur (max) | 0.035 | 0.03 | 0.035 |
| Silicon (max) | 1.00 | 0.50 | 0.50 |
| Nickel | 32.00–38.00 | 33.00–37.20 | 35.00–40.00 |
| Chromium | 19.00–21.00 | 22.00–26.00 | 22.50–25.00 |
| Molybdenum | 2.00–3.00 | 5.00–6.70 | 3.50–5.00 |
| Copper | 3.00–4.00 | 2.00–4.00 | 0.50–1.50 |
| Columbium (Nb) + Tantalum | 8xC-1.00 | – | 0.15–0.35 |
| Nitrogen | – | 0.10–0.16 | – |
| Iron | remainder | remainder | remainder |
*Iron is determined arithmetically by difference.
Mechanical Property Requirements
| Property | Value |
|---|---|
| Tensile Strength (min) | 80 ksi (550 MPa) |
| Yield Strength (0.2% offset, min) | 35 ksi (240 MPa) |
| Elongation in 2 in. or 50.8 mm or 4D (min) | 30.0% |
Yield strength shall be determined by the offset method at 0.2% limiting permanent set by Test Methods E8.
Technical Specifications
| Specification | Value |
| Standard | ASTM B729 Seamless Nickel-Iron-Chromium-Molybdenum-Copper Nickel Alloy Pipe and Tube |
| Grade | UNS N08020 (ATI Allvac Nickelvac 23, Alloy 20, Incoloy 020, Carpenter 20Cb-3, EN 2.4660), UNS N08026 (Carpenter 20Mo-6), UNS N08024 |
| Manufacturing Process | Hot Extrusion, Piercing, and Subsequent Cold Working |
| Seam Type | Seamless |
| Pipe Size | Outside Diameter (OD) Range: NPS 1/8″ -6″, Wall Thickness (WT) Range: 1.47 – 13.2mm |
| Length | 6000-12000mm |
| Delivery Condition | Stabilized-annealed condition, Solution-annealed condition, and Annealed condition |
| Heat treatment | UNS N08020 alloy in the stabilized-annealed condition. UNS N08026 alloy in the solution-annealed condition. UNS N08024 alloy in the annealed condition. |
| Inspection Certificate | EN 10204 Type 3.1 (Mill Test Certificate), EN 10204 Type 3.2 (Witness Testing or 3rd Party Inspection) |
| Test | Chemical analysis, Tensile test, Flattening test, Expansion test, Hydrostatic test, Nondestructive testing (NDT), Intergranular corrosion test, Metallographic examination |
Packing
Plain / Beveled Ends with Plastic Caps, Bundled or Loosely Packed.
Application
Chemical Processing: UNS N08020 and UNS N08026 are extensively used in the chemical processing industry due to their excellent resistance to sulfuric, phosphoric, and nitric acids. These materials are ideal for fabricating process equipment such as reactors, heat exchangers, and transfer piping.
Petrochemicals: In the petrochemical industry, these alloys are used in components that must withstand highly corrosive environments, including piping systems, valves, pumps, and storage tanks. Their resistance to chloride ion-induced stress corrosion cracking is particularly valuable.
Oil and Gas Production: The alloys are utilized in oil and gas extraction and processing where corrosive substances like sour crude oil and natural gas (which contain hydrogen sulfide) are present. Equipment such as these materials’ separators, scrubbers, and pumps can better resist corrosion and prolong service life.
Marine Engineering: Due to their superior resistance to seawater and saltwater environments, these alloys are suitable for marine applications, including shipbuilding and repair, desalination plants, and offshore oil rigs.
Pollution Control Equipment: UNS N08026, with its higher molybdenum content, is particularly suited for flue-gas desulfurization systems in power plants. It is used in ducts, scrubbers, dampers, and stack liners encountering hot, corrosive flue gases and airborne contaminants.
Pharmaceuticals: The seamless and non-reactive nature of ASTM B729 pipes ensures they can be used in environments requiring strict hygiene and resistance to aggressive cleaning agents, making them ideal for pharmaceutical product processing and transport systems.
Water Treatment: Both UNS N08020 and UNS N08026 are used in water treatment facilities, particularly in systems handling chlorinated water and brines, where corrosion resistance is critical.
